You can use the max online Q engines parameter with sp_config to control the maximum the number of Adaptive Server Q engines. For example:
sp_configure "max online Q engines", 4
Valid values are:
Minimum value – 0.
Default value – 0.
Maximum value – depends on the settings using sp_configure “max online engines".
The restrictions are:
max online Q engines cannot be greater than max online engines minus number of engines at startup.
The command fails if there is already an engine group referencing an engine in the range max online engines minus max online Q engines to max online engines minus 1.
For instance, if max online engines is 10 and you attempt to set max online Q engines to 4, an error is returned if there is an engine group bound to engines 6, 7, 8, or 9.
max online Q engines cannot be greater than max online engines.
Setting max online Q engines reserves the high range of max online engines for Q engines. Once you set max online Q engines, Adaptive Server engines cannot use the engines in the range that is reserved for Q engines. For example, if you set max online engines to 10, and set max online Q engines to 4, not only can Adaptive Server not use engines 6, 7, 8, and 9, but subsequent attempts to change number of engines at startup to 7, 8, or 9 fail, as do attempts to add engines 6, 7, 8, or 9 to an engine group.
Setting max online Q engines can
affect existing production environments. For this reason, Sybase
recommends that you increase max online engines by
the same value as you set max online Q engines.
For example, to set max online Q engines to 4,
increase max online engines by 4 also.
